parisc: sync compat getdents

Add VERIFY_WRITE check in the beginning like compat_sys_getdents() EFAULT on
parisc if put_user() fails.

Signed-off-by: Alexandr Andreev <aandreev@openvz.org>
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Grant Grundler <grundler@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

diff --git a/arch/parisc/kernel/sys_parisc32.c b/arch/parisc/kernel/sys_parisc32.c
index ce3245f..a8ebac4 100644 (file)
--- a/arch/parisc/kernel/sys_parisc32.c
+++ b/arch/parisc/kernel/sys_parisc32.c
@@ -350,6 +350,10 @@ sys32_getdents (unsigned int fd, void __user * dirent, unsigned int count)
        struct getdents32_callback buf;
        int error;
 
+       error = -EFAULT;
+       if (!access_ok(VERIFY_WRITE, dirent, count))
+               goto out;
+
        error = -EBADF;
        file = fget(fd);
        if (!file)
@@ -366,8 +370,10 @@ sys32_getdents (unsigned int fd, void __user * dirent, unsigned int count)
        error = buf.error;
        lastdirent = buf.previous;
        if (lastdirent) {
-               put_user(file->f_pos, &lastdirent->d_off);
-               error = count - buf.count;
+               if (put_user(file->f_pos, &lastdirent->d_off))
+                       error = -EFAULT;
+               else
+                       error = count - buf.count;
        }
 
 out_putf: